1. Field of Invention
The present invention relates to a zinc ferrite thin film and methods for manufacturing the same. More particularly, the present invention relates to electrochemical methods for manufacturing a zinc ferrite thin film.
2. Description of Related Art
Nano-sized zinc ferrite (zinc ferrite, ZnFe2O4) can be used as semiconductor material and photocatalyst material since it is capable of photo-electro conversion. As comparing with titanium dioxide with wide band gap (3.2 eV for anatase and 3.0 eV for rutile), nano-sized zinc ferrite has narrow band gap of about 1.9 eV and shows visible light absorption. Thus, nano-sized zinc ferrite has higher efficiency of sunlight utilization than neat titanium dioxide.
Generally, zinc ferrite can be formed on a substrate by a reactive sputtering technique and then annealed at a temperature of at least 500° C. to obtain the zinc ferrite thin film. Alternatively, powders of nano-sized zinc ferrite can be annealed at a temperature of at least 500° C. to obtain the zinc ferrite thin film. Methods for preparing said nano-sized zinc ferrite powders include sol-gel process, high temperature annealing process, and shock wave compress technique, etc.
Known methods for manufacturing the zinc ferrite thin film usually involves elaborate and costly apparatus and complicated process. Furthermore, said high annealing temperature limits the option of the material of the substrate and thus limits the application of the zinc ferrite thin film.
In view of the foregoing, there is a need to provide a method for manufacturing a zinc ferrite thin film, said method could employ less complicated apparatus and process and utilize lower annealing temperature than prior art does.